// Problem: 
// Contest: 
// URL: 
// Memory Limit: 
// Time Limit: 
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#include<bits/stdc++.h>
using namespace std;
#define int long long
inline int read(){
	int s=0,w=1;
	char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')w=-1;ch=getchar();}
	while(ch>='0'&&ch<='9') s=s*10+ch-'0',ch=getchar();
	return s*w;
}
signed main()
{
	int T=1;
//	cin>>T;
	while(T--)
	{
		int mod=1e6+7;
		int n,m;
		cin>>n>>m;
		vector<int> v(n+1),dp(m+1);
		for(int i=1;i<=n;i++)cin>>v[i];
		//vector<vector<int>> dp(n+1,vector<int>(m+1));
		dp[0]=1;
		for(int i=1;i<=n;i++)
		{
			for(int j=m;j>=0;j--)
			{
				for(int k=1;k<=min(j,v[i]);k++)
				{
					dp[j]=(dp[j]+dp[j-k])%mod;
				}
			}
		}
		cout<<dp[m];
	}
	return 0;
}
